For mobile communication terminal antennas, various models for performing the following properties have been proposed. In order to accomplish high efficiency, low loss, compact and lightweight structure, omni-directionality of radiation pattern, impedance matching for increasing radiation efficiency, packaging technology for design simplification, low cost, human body protection technology from radiation, wide bandwidth, low power consumption, improved technology appropriate to electromagnetic environment, etc., various kinds of antenna technologies have been developed.
Along with the slimming and miniaturization of mobile communication terminals, the size of the antenna has also decreased. At this point, technology capable of minimizing the size of the antenna while still maintaining the same function is one of the most important technologies.
Conventional mobile communication terminal antennas such as monopole antennas, whip antennas, helical antennas, sleeve antennas, inverted F antennas, diversity antennas, micro-strip antennas, chip antennas, twisted loop antennas, EID antennas, N-type antennas, etc., have been developed.
Such antennas may be classified as either internal or external antennas depending on the installation position. External antennas include monopole antennas, whip antennas, helical antennas, sleeve antennas, N-type antennas, chip antennas, FS-FIFI antennas, etc., all of which are installed at the exterior of terminals.
Internal antennas include inverted F antennas, planar inverted F antennas, diversity antennas, micro-strip antennas, twisted loop antennas, EID antennas, etc., all of which are installed in the interior of terminals.
Planar antennas may be classified further as inverted F antennas, planar inverted F antennas, diversity antennas, micro-strip antennas, EID antennas, FS-FIFA antennas, RCDLA antennas, or DTSA antennas, all of which have a planar structure.
In the conventional planar antennas, since the size of the antenna has also decreased with the slimming and miniaturization of mobile communication terminals, it is difficult to minimize the size of the antenna while still maintaining the same function.